Incidental synchronous intrathyroidal parathyroid carcinomas and papillary thyroid microcarcinoma with compressive neck mass and primary hyperparathyroidism: case report and literature review.

BACKGROUND: Parathyroid carcinoma (PC) is a rare malignancy, often diagnosed incidentally through postoperative pathological examination. The occurrence of nodular goiter, intrathyroidal parathyroid carcinoma, contralateral parathyroid adenoma (PA), and papillary thyroid microcarcinoma (PTMC) is extremely uncommon, which prompted us to report our case experience. CASE PRESENTATION: We describe a 67-year-old male who presented with a cervical mass causing tracheal compression, which prompted him to seek medical advice. Based on preoperative auxiliary examination results from color Doppler ultrasound, SPECT parathyroid imaging, and blood tests, he was initially diagnosed with a suspected parathyroid adenoma and nodular goiter. Excision of the right lobe and isthmus of the thyroid, and left superior parathyroid gland was conducted, which were sent to intraoperative frozen pathological examination. During intraoperative observation, adhesion around the right thyroid lobe was discovered. Consequently, right central area lymph node dissection was performed due to suspicion of an aggressive malignant tumor. Histology and immunohistochemistry analysis revealed incidental intrathyroidal parathyroid carcinoma, contralateral parathyroid adenoma, classical papillary thyroid microcarcinoma, and nodular goiter. CONCLUSION: Parathyroid carcinoma should be highly suspected when extremely high levels of PTH and severe hypercalcemia are present, which cannot be simply explained by a preoperatively localized parathyroid adenoma, especially when suspicious malignant adhesion is found during intraoperative exploration. In cases where multifocal thyroid nodules are associated with increased uptake of 99Tc-sestamibi, the possibility of coexisting carcinomas should be considered, not only for thyroid malignancy but also for the potential presence of intrathyroidal parathyroid carcinoma.

Ectopic Intrathyroidal Parathyroid Adenoma Presenting With Osteoporotic Fractures in a Young Man: A Case Report.

Primary hyperparathyroidism (PHPT) can be associated with osteoporosis (OP) and fractures. We present a case of a 49-year-old male referred to our osteoporosis outpatient clinic due to a right femur osteoporotic fracture. At the age of 38, a right plantar nodular lesion was excised, and its histology was compatible with a deep dermis nodule formed by mononuclear and giant osteoclast-like cells. He has reported osteoporotic fractures since age 39 and renal colic episodes since age 45. His father had lipomas and renal colic episodes, and his paternal grandmother had lipomas. The laboratory evaluation was compatible with PHPT. A cervical ultrasound showed a 10mm single solid nodule in the left thyroid lobe, strongly hypoechogenic, with microcalcifications. Its cytology showed parathyroid tissue without atypia. Parathyroid scintigraphy had no uptake. A dual-energy X-ray absorptiometry scan showed a femoral neck Z-score of -4.3. He started alendronate/cholecalciferol (70mg/5600IU) weekly. He was submitted to a left hemithyroidectomy. Its histology showed an intrathyroidal parathyroid adenoma. Ectopic parathyroid adenomas are rare, of which 0.7%-6% are intrathyroidal. The excised foot lesion could be a brown tumour. Furthermore, calcium metabolism evaluation at that time might have allowed a PHPT diagnosis and its morbidity prevention. Osteoporotic fractures in young men must alert to secondary OP.

Hyperfunctioning Intrathyroidal Parathyroid: a Misleading Preoperative Diagnosis.

Hyperfunctioning parathyroid glands may be rarely located in the thyroidal parenchyma and not identified by imaging or during surgical procedures. We present three patients with primary hyperparathyroidism related to hyperfunctioning intrathyroidal parathyroid retrospectively selected among 732 cases from own Institutional parathyroid PET/CT registry from 2018 to 2022. Intrathyroidal parathyroids showed intense 18F-fluorocholine uptake but a variable echographic pattern, inconstant 99mTc-MIBI uptake, and atypic iodine-contrast enhancement. Although rare, the possibility of an intrathyroidal parathyroid should be considered when no hyperfunctioning gland is found on preoperative imaging and thorough bilateral neck exploration.

An Unusual Case of Primary Hyperparathyroidism: Case Report of a Bifocal Intrathyroidal Parathyroid Carcinoma.

Intrathyroidal parathyroid carcinoma is an extremely rare cause of primary hyperparathyroidism. We reported a 51-year old woman who presented symptoms of hypercalcemia. 99mTc sestamibi single-photon emission computed tomography/computed tomography (CT) revealed a large hypermetabolic nodule in the left thyroid lobe suggestive of hyperfunctioning parathyroid tissue. 11C-methionine positron emission tomography/computed tomography (PET/CT) and 18F-fluorocholine PET/CT confirmed the nodule in the left thyroid lobe and also revealed a hypermetabolic activity on the posterior surface of the lower left pole. The patient underwent a total thyroidectomy and parathyroidectomy, and a diagnosis of bifocal intrathyroidal parathyroid carcinoma was confirmed. We present the first reported case of bifocal intrathyroidal carcinoma and discuss the discordant imaging results.

Diagnosis of Ectopic Intrathyroidal Parathyroid Adenoma with Nodular Goiter by 18F Fluorocholine: A Case Report.

The occurrence of ectopic intrathyroidal parathyroid adenoma (EPTA) is very rare, which causes some difficulties in diagnosis and complicates treatment. In addition, the occurrence of EPTA with nodular goiter (NG) is rare, which makes diagnosis difficult and requires the assistance of clinical evidence, imaging data, and cytological examination results. Therefore, we present a patient with a final diagnosis of ETPA with NG.

Intrathyroidal Parathyroid Carcinoma: Case Report and Literature Review.

Intrathyroidal parathyroid carcinoma (PC) is a rare malignancy that is usually difficult to diagnose. We present a case of a 31-year-old male with a history of hyperparathyroidism who was found to have intrathyroidal PC upon review of immunostains along with a review of the current literature. A systematic review of the literature utilizing the PubMed database identified 24 relevant, full-text articles. 25 cases were analyzed, including our own report. The case of a 31-year-old man with a history of hyperparathyroidism managed with subtotal thyroidectomy and subtotal parathyroidectomy who had persistent hypercalcemia and elevated parathyroid hormone. Abnormal radiotracer uptake was noted in the left thyroid gland. Neck exploration with left parathyroidectomy and revision thyroidectomy was performed. A candidate left inferior parathyroid was found within the left thyroid lobe remnant and identified as parathyroid carcinoma. Immunostains determined an intrathyroidal parathyroid carcinoma. The literature review shows the average presenting age was 50.9 years. 54.17% (CI, 43-82%) of affected patients are female. Right-sided thyroid involvement is seen in 54.17% (CI, 34-74%) of cases. The inferior aspect of the thyroid is involved in 66.67% of cases (CI, 53-89%). Intrathyroidal parathyroid carcinoma is a rare and challenging diagnosis due to similarities with other more common endocrine abnormalities. This review found that the inferior parathyroid is more likely to be located within the thyroid gland. Surgeons may consider aberrant anatomical locations, including intrathyroidal locations, for the inferior parathyroid glands.

The Value of Preoperative and Intraoperative Ultrasound in the Localization of Intrathyroidal Parathyroid Adenomas.

AIM: Intrathyroidal parathyroid adenoma (IPA) is rare and may easily be mistaken for thyroid nodule in ultrasonography. The aim of this study was to investigate the characteristic features of IPA and explore the value of preoperative and intraoperative ultrasound in the diagnosis and localization of IPA. METHODS: 13 of 216 patients who were found to have intrathyroidal parathyroid lesions underwent parathyroidectomy in our hospital because of PHPT. According to the relationship between parathyroid adenoma and thyroid gland, parathyroid adenoma was divided into extra-thyroid type or intra-thyroid type (partial or complete) and the results were compared with surgical and histopathological reports as gold standard. The sonographic features of intrathyroidal parathyroid lesions were analyzed retrospectively. RESULTS: A total of 12 intrathyroidal lesions showed profoundly hypoechoic solid nodules with well-defined border, abundant blood flow and polar feeding vessels originating from the superior or inferior thyroid artery (92.3%, 12/13). These nodules were finally confirmed as IPA (or IPAC) after surgery. Polar feeding vessel was not detected in one case of parathyroid hyperplasia confirmed by pathology (7.7%, 1/13). 12 cases were diagnosed and localized on ultrasonography before operation and 10 cases were localized on Tc-99m MIBI SPECT/CT. CONCLUSIONS: The color Doppler ultrasound findings of IPA were confirmed as profoundly hypoechoic nodules with clear boundary and abundant internal blood flow. The presence of polar feeding vessels which originate from thyroid artery were identified as characteristic features of US for IPA. Preoperative and intraoperative ultrasound could be helpful in the localization and treatment of intrathyroidal parathyroid diseases.

Co-occurrence of bilateral intrathyroidal parathyroid gland and papillary thyroid carcinoma; a case report.

INTRODUCTION: Intrathyroidal parathyroid is a parathyroid completely embedded within the thyroid parenchyma. The aim of this study is to present a case with co-occurring bilateral normal intrathyroidal parathyroid glands and papillary thyroid carcinoma (PTC). CASE PRESENTATION: A 35-year-old female presented with anterior neck swelling for a duration of a week. The patient was generally asymptomatic. Ultrasound showed mild enlargement of the thyroid gland, and a well-defined solid nodule measuring 9 ∗ 8 ∗ 7 mm in the left lobe with malignant characteristics. Laboratory findings were within normal limits. Fine needle aspiration of the nodule resulted in the diagnosis of PTC. The patient underwent total thyroidectomy. Histological examination confirmed the diagnosis of well differentiated multifocal bilateral PTC alongside two bilaterally located intrathyroidal parathyroid glands. DISCUSSION: The occurrence of normal ITP is exceedingly rare, and even rarer when simultaneous with other thyroidal lesions. It is theorized that inferior parathyroid glands arise from the third pharyngeal pouch, and during embryogenesis they might migrate to other anatomic locations. In this case, two bilateral normal ITP were present with PTC. CONCLUSION: Normal ITP presents a diagnostic challenge due to their high insensitivity to current preoperative diagnostic techniques; hence, surgeons are required to carefully examine thyroid tissue during thyroidectomy when missing parathyroid glands are observed.

Synchronous intrathyroidal parathyroid carcinoma and thyroid carcinoma: case report and review of the literature.

BACKGROUND: Parathyroid carcinoma is a rare endocrine malignancy, rarer when synchronous with a non medullary well differentiated thyroid carcinoma. Parathyroid carcinoma accounts of 0.005% of all malignant tumors and it is responsible for less than 1% of primary hyperparathyroidism. The intrathyroidal localization of a parathyroid gland is not frequent with a reported prevalence of 0.2%. Carcinoma of parathyroids with intrathyroidal localization represents an even rarer finding, reported in only 16 cases described in literature. The rare constellation of synchronous parathyroid and thyroid carcinomas has prompted us to report our experience and perform literature review. CASE PRESENTATION: We herein report a case of a 63-years-old man with multinodular goiter and biochemical diagnosis of hyperparathyroidism. Total thyroidectomy with radio-guide technique using gamma probe after intraoperative sesta-MIBI administration and intraoperative PTH level was performed. The high radiation levels in the posterior thyroid lobe discovered an intrathyroidal parathyroid. Microscopic examination revealed a parathyroid main cell carcinoma at the posterior thyroidal left basal lobe, a classic papillary carcinoma at the same lobe and follicular variant of papillary carcinoma at the thyroidal right lobe. To the best of our knowledge, this is the first case documenting a synchronous multicentric non medullary thyroid carcinomas and intrathyroidal parathyroid carcinoma. CONCLUSIONS: Our experience was reported and literature review underlining challenging difficulties in diagnostic workup and surgical management was carried out.

Intrathyroidal parathyroid carcinoma: a case report and literature review.

Parathyroid carcinoma is an uncommon endocrine malignancy comprising 0.5%-2% of patients with primary hyperparathyroidism. The probability of an intrathyroidal location is low (0.2%) and make preoperative suspicion and diagnosis challenging. Less than 20 cases of intrathyroidal parathyroid carcinoma have been reported. We introduce a case of intrathyroidal parathyroid carcinoma mimicking a suspicious thyroid nodule, and review the literature, with a focus on the role of adjuvant radiotherapy.

Neuroendocrine Tumors of the Thyroid and Their Mimics.

This paper will review neuroendocrine lesions of the thyroid and the differential diagnosis with the most significant such tumor of the thyroid, that is, medullary thyroid carcinoma. A brief overview of the understanding of this tumor's identification as a lesion of C cells and its familial and syndromic associations will be presented. Then, a discussion of the various mimics of medullary carcinoma will be given with an approach to the types of tests that can be done to arrive at a correct diagnostic conclusion. This review will focus on practical "tips" for the practicing pathologist.

Fine needle aspiration of an intrathyroidal parathyroid carcinoma mimicking a primary thyroid anaplastic carcinoma: A case report with review of the literature.

Intrathyroidal parathyroid carcinoma is an uncommon malignancy. A 46-year-old male presented with a left neck mass. Computed tomography (CT) scan revealed a hypodense mass in the left thyroid lobe along with evidence of metastatic lymphadenopathy. Aspiration of the left thyroid nodule was performed, and a diagnosis of malignancy was rendered, favoring a primary anaplastic carcinoma. Based on the cytologic diagnosis, the patient underwent a total thyroidectomy. Before the surgery, intact parathyroid hormone (PTH) and calcium level (PTH = 78 pg/mL; Calcium = 10.6 mg/dL) were found to be minimally elevated. On gross examination, a 3.2 cm mass within the left inferior thyroid lobe was seen. Histopathologic examination and ancillary studies supported the diagnosis of a parathyroid carcinoma. We, hereby present, an exceedingly rare presentation of an intrathyroidal parathyroid carcinoma with only minimal elevation of PTH and calcium, mimicking a primary anaplastic thyroid carcinoma on cytologic examination.

Atypical presentations of parathyroid gland pathology: A pictorial review.

Primary hyperparathyroidism is associated with significant morbidity and mortality. It is in this day and age, an eminently treatable condition which relies heavily on preoperative imaging to localise enlarged parathyroid glands. The imaging appearances of parathyroid gland enlargement are varied; this paper seeks to address some of its more unusual manifestations with an emphasis on its atypical enhancement patterns, mimics and associations. An enlarged glands may also present as an 'incidentaloma' in head and neck imaging performed for entirely different indications, or as part of sporadic or familial syndrome. Radiologists are in a good position to expedite the relevant investigations and curative treatment, and knowledge of the spectrum of imaging appearances is crucial.

Simultaneous intrathyroidal parathyroid adenomas and multifocal papillary thyroid carcinoma in a patient with kidney transplantation: a case report.

BACKGROUND: Persistent hyperparathyroidism after kidney transplantation has been associated with adverse outcomes. Parathyroidectomy is the definitive treatment approach, but the success of parathyroidectomy relies on the accurate preoperative localization of the culprit parathyroid lesions. Simultaneous intrathyroidal parathyroid adenomas and multifocal papillary thyroid carcinoma present important diagnostic challenges. Here, we describe a patient with kidney transplantation who underwent successful surgery after being evaluated with functional and structural imaging. CASE PRESENTATION: A 53-year-old man presented with potentially malignant multifocal thyroid nodules by ultrasonography 2 years after kidney transplantation. The patient had hypercalcaemia and persistent hyperparathyroidism. Thyroid papillary carcinoma was confirmed in the left thyroid nodules by fine-needle aspiration biopsy. The right superior thyroid hypoechoic nodule was 1.2 cm in size and showed marked uptake of the tracer 99mTcO4-sestamibi during single-photon emission computed tomography/computed tomography (SPECT/CT); additionally, a cystic parathyroid lesion without tracer uptake was present behind the left superior pole of the thyroid. The histological examination demonstrated the coexistence of right intrathyroidal parathyroid adenomas, left cystic parathyroid nodular hyperplasia and multifocal papillary thyroid carcinoma. At the 6-month follow-up, the serum calcium levels were within the normal range, and the patient's kidney function remained stable. CONCLUSIONS: Simultaneous intrathyroidal parathyroid adenomas and multifocal papillary thyroid carcinoma in a patient with kidney transplantation is a rare clinical scenario. Physicians must be aware that the combination of functional (SPECT/CT) and structural (ultrasonography) imaging is highly successful in diagnosing patients with coexistent intrathyroidal parathyroid adenomas and papillary thyroid carcinoma.

Intrathyroidal parathyroid adenoma: Diagnostic pitfalls on fine-needle aspiration: Two case reports and literature review.

Parathyroid adenomas may occur within the thyroid, clinically simulating thyroid nodules. Fine-needle aspiration (FNA) of these presumably "thyroid nodules" can lead to misinterpretation of cytomorphological findings because of similarities in cytological features of parathyroid and thyroid lesions. Here, we reported two cases of intrathyroidal parathyroid adenomas. One of them was misinterpreted as thyroid lesions. The other was composed exclusively of oncocytic cells and had a correct cytological diagnosis. In this study, both cases showed a new cytological feature which has not been reported in the literature: many capillaries protruding outside the three-dimensional fragments without epithelial cells around. Diagn. Cytopathol. 2016;44:921-925. © 2016 Wiley Periodicals, Inc.

Life-threatening intrathyroidal parathyroid adenoma.

Acute primary hyperparathyroidism and parathyroid crisis are characterized by life-threatening hypercalcemia, a rare disorder. A 69-year-old female patient presented at our hospital's neurology clinic with weakness, nausea, vomiting, depression, and hypercalcemia. Treatment of hypercalcemia resulted in no improvement in neurological symptoms, indicating resistance to treatment. Thyroid ultrasonography and parathyroid scintigraphy revealed hypoechoic nodules in the right lobe, pieces of nodules in the left lobe, and high serum calcium and parathyroid hormone levels. After provision of intensive medical treatment including hydration, diuresis, and bisphosphonate infusion resulted in only minimal decrease in the calcium level, urgent surgical treatment was performed. Frozen biopsy of the right intrathyroidal giant parathyroid adenoma in the right lobe confirmed initial diagnosis of primary hyperparathyroidism. Based on the biopsy findings, right parathyroidectomy and right total and left subtotal thyroidectomy were performed. Histopathologic examination revealed a parathyroid adenoma localized inside large thyroid nodules. Review of the findings resulted in diagnosis of intrathyroidal parathyroid adenoma. Symptoms of hypercalcemia improved rapidly during the postoperative period.

[Contribution of intraoperative scintigraphy to the detection of intrathyroidal parathyroid adenoma]. / Aportación de la gammagrafía intraoperatoria en la detección del adenoma paratiroideo intratiroideo.

The intrathyroidal parathyroid adenomas (IPA) represent a rare cause of primary hyperparathyroidism whose location difficults appropriate surgical removal. We present the case of a patient diagnosed of parathyroid adenoma by presurgical scintigraphy in which finally during the parathyroidectomy, the lesion location was intrathyroidal. We consider that the intrasurgical parathyroid scintigraphy with (99m)Tc-MIBI by portable gammacamera is useful in the parathyroid adenomas removal and essential in the case of IPA.

Giant intrathyroidal parathyroid adenoma.

Primary hyperparathyroidism (PHPT) is not an uncommon endocrine disorder. However, acute primary hyperparathyroidism, or parathyroid crisis (PC), is a rare clinical entity characterized by life-threatening hypercalcemia of a sudden onset in patients with PHPT. We describe a patient with PC who presented with acute worsening of depressive symptoms, nausea and vomiting, and required emergency surgery. Serum calcium, alkaline phosphatase, and parathyroid hormone were elevated and serum phosphorus was low. An emergency hemithyroidectomy was performed because of none medical control of hypercalcemia. A giant intrathyroidal parathyroid adenoma was diagnosed. PHTP can be a life-threatening situation for patients, requiring immediate surgical treatment. A giant intrathyroidal parathyroid adenoma is an uncommon cause of PC.